In-home theater surround sound speaker system

Abstract

An apparatus for realistically reproducing sound, particularly for sound based on a stereophonic signal having dialog and effects and associated with an accompanying video image. The apparatus includes a front speaker located in proximity to the video image for providing acoustic output based upon a summation signal of the component left and right (L+R) channels of the audio signal. A rear speaker located to the rear of the viewing area provides acoustic output based upon a difference signal, (L-R) or (R-L), between the left and right channels. Left and right speakers located to the respective left and right sides of the viewing area output audio based upon the respective left or right channels. The left and right channels speakers reproduce in one embodiment the respective left and right channels of the audio signal and in a second embodiment reproduce a difference signal, (L-R) or (R-L). Output to the left and right speakers is band limited to substantially filter out frequency components below a predetermined threshold. A bass speaker may also be provided to output the low frequency components of a (L+R) summation signal. The (L+R) summation signal input assists in localizing dialog to the front speaker, in proximity to the video image. The (L-R) or (R-L) difference signal substantially removes dialog sound so that the side and rear speaker output primarily comprises sonic ambience and surround sound effects. Band limiting the left and right speakers further assists in localizing dialog to the video image.

What is claimed is: 
     
       1. A speaker system for reproducing a stereophonic audio signal generated by an audio signal source, comprising: a front speaker for providing an acoustic output in response to a (L+R) input signal, where L is a left channel signal of the stereophonic signal and R is a right channel signal of the stereophonic audio signal;   a rear speaker for providing an acoustic output in response to an input signal varying defined as a difference between the left and right channel signals;   means for filtering the left channel signal to substantially eliminate low and midrange acoustic frequencies;   a left satellite speaker for providing an acoustic output substantially only in response to the filtered left channel signal;   means for filtering the right channel signal to substantially eliminate low and midrange acoustic frequencies;   a right satellite speaker for providing an acoustic output substantially only in response to the filtered right channel signal; and   a bass speaker for providing low frequency acoustic output in response to at least one of the group of the L and R input signals.   
     
     
       2. The apparatus as defined in claim 1 further comprising an interconnect module for receiving the left and right channel signals from the audio signal source and distributing the left and right channel signals to the speakers in a predefined manner. 
     
     
       3. The apparatus as defined in claim 2 wherein the interconnect module further comprises: an input connector for engaging a corresponding connector of an input cable for providing the stereophonic audio signal from the audio signal source;   a plurality of first output connectors for engaging a corresponding plurality of connectors of a plurality output cables for providing an audio signal to each of the bass and center speakers; and   a plurality of second output connectors for engaging a corresponding plurality of connectors of a plurality of output cables for providing an audio signal to each of the left, right, and center speakers, the input connector and the first and second output connectors differing to insure proper connection by an operator of the input and output cables to the interconnect module.   
     
     
       4. The apparatus as defined in claim 3 wherein the interconnect module and the bass speaker are integrated to define one component housing both the bass speaker and the interconnect module. 
     
     
       5. The apparatus as defined in claim 1 further comprising an amplifier for receiving and amplifying the left and right channel signals prior to application to the respective speakers. 
     
     
       6. The apparatus as defined in claim 1 wherein the means for filtering input to the left and right satellite speakers are substantially identical and further comprise first order filters. 
     
     
       7. The apparatus as defined in claim 1 wherein the means for filtering input to the left and right satellite speakers are substantially identical and further comprise second order filters. 
     
     
       8. The apparatus as defined in claim 1 wherein the center speaker further comprises: a transducer for providing acoustic output from the center speaker, the transducer having first and second voice coils, the first voice coil being responsive to the left channel signal, and the second voice coil responsive to the right channel signal;   wherein the acoustic output of the transducer provides a resultant (L+R) audio signal.   
     
     
       9. The apparatus as defined in claim 1 wherein the center speaker further comprises: a first transducer for providing acoustic output from the center speaker, the first transducer having a first voice coil responsive to the left channel signal; and   a second transducer for providing acoustic output from the center speaker, the second transducer having a second voice coil responsive to the right channel signal;   wherein the acoustic output of the first and second transducers substantially combined to provide a resultant (L+R) audio signal.   
     
     
       10. The apparatus as defined in claim 1 wherein the rear speaker further comprises: a transducer for providing acoustic output from the rear speaker, the transducer having a voice coil including a first, positive terminal to which is applied the left channel signal and a second, negative terminal to which is applied the right channel signal;   wherein the acoustic output of the transducer provides a resultant (L-R) audio signal.   
     
     
       11. The apparatus as defined in claim 1 wherein the rear speaker further comprises: a transducer for providing acoustic output from the rear speaker, the transducer having a first voice coil responsive to a first channel signal and a second voice coil responsive to a second channel signal, the second voice coil having the second channel signal applied thereto in a polarity opposite the polarity of the first channel signal applied to the first voice coil;   wherein the transducer provides an acoustical output signal varying in accordance with a difference between the first and second signal.   
     
     
       12. The apparatus as defined in claim 1 wherein the left satellite speaker provides an acoustic output in response to a first difference signal defined in accordance with a difference between the left and right channel signals and the right satellite speaker provides an acoustic output in response to a difference signal defined in accordance with a second difference signal defined in accordance with a difference between the left and right channel signals. 
     
     
       13. The apparatus as defined in claim 12 wherein the first and second difference signals are substantially identical and the difference signal is defined as one of (L-R) and (R-L) signals. 
     
     
       14. The apparatus as defined in claim 12 wherein one of the difference signals is defined as a (L-R) signal and the other difference signal is defined as a (R-L) signal. 
     
     
       15. The apparatus as defined in claim 12 further comprising: a left high pass filter for passing to the left satellite speaker substantially only high audio frequencies of the first difference signal; and   a right high pass filter for passing to the right satellite speaker substantially only high audio frequencies of the second difference signal.   
     
     
       16. The apparatus as defined in claim 15 wherein the left and right high pass filters are substantially identical and further comprise a capacitor in series with a positive input terminal of the audio signal applied to the satellite speaker. 
     
     
       17. The apparatus as defined in claim 15 wherein the left and right high pass filters are substantially identical and further comprise: a capacitor in series with the positive terminal of each satellite speaker; and   an inductor in shunt across the positive and negative terminals of each satellite speaker.   
     
     
       18. The apparatus as defined in claim 1 wherein the means for filtering the left channel signal eliminates acoustic frequencies below 1 kilohertz (KHz), and the means for filtering the right channel signal eliminates acoustic frequencies below 1 kilohertz (KHz). 
     
     
       19. A speaker system for reproducing a stereophonic audio signal generated by an audio signal source and associated with a companion video signal, comprising: a signal preprocessor for generating summation and difference ((R-L) or (L-R)) output signals based upon a L and R input signal, where L is a left channel signal of the stereophonic signal and R is a right channel signal of the stereophonic audio signal;   a first speaker for providing an acoustic output in response to the summation output signal;   first means for filtering the difference signal to substantially eliminate low and midrange acoustic frequencies;   a second speaker for providing an acoustic output substantially only in response to the first filtered difference signal;   second means for filtering the difference signal to substantially eliminate low and midrange acoustic frequencies;   a third speaker for providing an acoustic output substantially only in response to the second filtered difference signal; and   a fourth speaker for providing an acoustic output in response to the difference output signal.   
     
     
       20. The apparatus as defined in claim 19 further comprising a fifth speaker for providing low frequency acoustic output in response to the summation output signal. 
     
     
       21. The apparatus as defined in claim 19 further comprising an amplifier for receiving and amplifying the left and right channel signals prior to application to the respective speakers. 
     
     
       22. The apparatus as defined in claim 19 wherein the first and second means for filtering are substantially identical and further comprise a first order filter. 
     
     
       23. The apparatus as defined in claim 19 wherein the first and second means for filtering are substantially identical and further comprise a second order filter. 
     
     
       24. The apparatus as defined in claim 19 wherein the preprocessor outputs an (L-R) difference signal input to he second, third, and fourth speakers. 
     
     
       25. The apparatus as defined in claim 19 wherein the preprocessor outputs an (L-R) difference signal input to one of the second and third speakers and to the fourth speaker, and the difference signal is applied to the other of the second and third speakers with a reverse polarity. 
     
     
       26. The apparatus as defined in claim 19 wherein the preprocessor outputs an (R-L) difference signal input to one of the second and third speakers and to the fourth speaker, and the difference signal is applied to the other of the second and third speakers with a reverse polarity. 
     
     
       27. The apparatus as defined in claim 19 wherein the preprocessor outputs an (L+R) summation signal input to the first speaker. 
     
     
       28. The apparatus as defined in claim 19 wherein the first means for filtering the left channel signal eliminates acoustic frequencies below 1 kilohertz (KHz), and the second means for filtering the right channel signal eliminates acoustic frequencies below 1 kilohertz (KHz). 
     
     
       29. A speaker system for reproducing a stereophonic audio signal having component left and right channel input signals, comprising: a front speaker for providing an acoustic output in response to a (L+R) summation signal, where L is a left channel signal of the stereophonic signal and R is a right channel signal of the stereophonic signal;   a pair of side speakers for providing acoustic output in response to the component input signals, where the component input signals are filtered prior to application to the side speakers so that substantially only high frequency portions of the component input signals are output by the side speakers;   a rear speaker for providing acoustic output in response to a (L-R) difference signal of the component input signals;   a wireless interconnect module for receiving the left and right channel signals and wirelessly distributing selected combinations of the left and right signals to particular speakers, the wireless interconnect module including at least one transmitter for transmitting a selected combination of the output signals to the respective speakers; and   a receiver associated with a particular speaker for receiving the transmitted signal from the at least one transmitter, the receiver receiving the transmitted signal and outputting an electronic signal input to the speaker.   
     
     
       30. The apparatus as defined in claim 29 further comprising a fifth speaker for providing low frequency acoustic output in response to a summation signal of the component input signals. 
     
     
       31. The apparatus as defined in claim 30 wherein the fifth speaker is responsive to a summation (L+R) input signal, where L is a left channel signal of the stereophonic signal and R is a right channel signal of the stereophonic audio signal. 
     
     
       32. The apparatus as defined in claim 29 wherein the pair of side speakers is responsive to a (L-R) difference signal ((R-L) or (L-R)), where L is a left channel signal of the stereophonic signal and R is a right channel signal of the stereophonic audio signal. 
     
     
       33. The apparatus as defined in claim 32 wherein the rear speaker is responsive to the difference signal. 
     
     
       34. The apparatus as defined in claim 29 wherein the front speaker is responsive to a summation (L+R) input signal, where L is a left channel signal of the stereophonic signal and R is a right channel signal of the stereophonic audio signal. 
     
     
       35. The apparatus as defined in claim 29 wherein the side speakers are filtered to substantially eliminate frequencies below 1 kilohertz (KHz).